Ben Siller of Denver Environmental Health uses the Nasal Ranger, a device that helps officials detect the intensity of an odor, in November 2013 in Denver. (Hyoung Chang, Denver Post file)

Airing it out: Rules target Denver grows’ weed smells

A beefed-up odor-control ordinance that would require marijuana grow houses to reduce the smells they emit won approval Tuesday from a Denver City Council committee.

The proposal fits into a larger council discussion about ways to limit the industry’s impact on neighborhoods that are saturated with marijuana businesses. About 1 a.m. Tuesday, the full council deadlocked 6-6 on a proposal to set location caps for pot shops and cultivation facilities. That licensing measure could be reintroduced for more discussion next Monday.

While council members have struggled to find consensus on licensing, the odor measure was advanced easily at the afternoon Safety & Well-being Committee meeting.

The city’s Department of Environmental Health says the expanded ordinance would add nearby business owners and their employees to the list of people can file formal complaints about an offending facility’s odors; currently only residents can file complaints. The city must receive five complaints about a facility to trigger inspection and enforcement, but the proposal would extend the period for that threshold to be met from 12 hours to 30 days.

The most proactive measure is a proposed requirement for certain businesses, including marijuana growing, processing or manufacturing operations, to submit odor-control plans to the city. Those would describe any odors expected to originate at the business and, if necessary, a plan to use technology to prevent the odor’s emission, such as air scrubbers.

Businesses also would have to file such a plan if they manufacture pet food, process meat byproducts, manufacture asphalt shingles or coating materials, refine oil, preserve wood or treat sewage. And odor-control plans could be required if a facility receives too many complaints or exceeds odor thresholds in testing.

If the full council approves the proposal on May 2, the health department plans to convene an odor advisory group to adopt detailed odor rules by early next year. The requirement for odor-control plans would take effect 90 days later.

Some in the marijuana industry have protested the new rules because odor-control equipment could prove costly. Neighborhood advocates have pushed for the changes, as have some council members.

But Councilman Albus Brooks, before voting early Tuesday against the marijuana licensing proposal, brought up the odor ordinance. He cautioned against believing it would eliminate marijuana odor problems entirely in some areas.

“When you begin to saturate and when you begin to concentrate (businesses), there’s no smell ordinance that can identify where this is coming from,” said Brooks, adding that he lives 800 feet from a grow house in Cole. “And I’ve never seen a council so sure of a bill that hasn’t even come through committee yet.”

Jon Murray: 303-954-1405, or @JonMurray

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